Institution: | 1.Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry, College of Stomatology,Xi’an Jiaotong University,Xi’an,People’s Republic of China;2.Department of Oral Pathology, College of Stomatology,Ningxia Medical University,Yinchuan,People’s Republic of China |